A question raised by the Talmud is:
Why was it so rare that great scholars had illustrious sons or descendants?
The point is that there is no guarantee of the continuation of trends.
Therefore, it is of no importance and of no avail to consider one given family or race as superior to another.
–Rabbi Adin Steinsaltz
From On Being Free, p. 82, by Rabbi Adin Steinsaltz